The surgical removal of part of the breast with a cancerous tumor (lumpectomy), breast tissue, or the entire breast. In some cases, lymph nodes are also removed. In rare cases, some of the chest muscles are removed as well.

The surgical removal of part of the breast with a cancerous tumor (lumpectomy), breast tissue, or the entire breast. In some cases, lymph nodes are also removed. In rare cases, some of the chest muscles are removed as well.